The jury in the murder trial of Andrew Nichols has retired to consider its verdict.
Mr Nichols denies murdering electrical engineer Colin Bolton, 28, on the Kingsnympton estate last year but admits inflicting the killing blow.
Judge Peter Rook QC, in summing up the case, told jurors the key point they had to consider was whether Mr Nichols, 45, had lost his self-control when he stabbed Mr Bolton to death.
Mr Bolton had "goaded" the defendant after sleeping with his girlfriend, Michelle Dooley, the Old Bailey heard last week, including by handing over a photo of the pair kissing.
That photograph showed them in a "provocative pose", defence barrister Lewis Power QC said.
The jury was sent out shortly after 12.30pm today.